SQRT

import java.io.*;
import java.util.Arrays;
import java.util.Comparator;
import java.util.StringTokenizer;

public class SolSqrt {
    FastScanner in;
    PrintWriter out;

    class Cell {
        long currentStart;
        long atLeast;
        int pos;

        public Cell(long currentStart, long atLeast, int pos) {
            this.currentStart = currentStart;
            this.atLeast = atLeast;
            this.pos = pos;
        }

        public long getValue(long currentAdd) {
            return Math.max(atLeast, currentStart + currentAdd);
        }
    }

    long whenSecondSmaller(Cell c1, Cell c2) {
        if (c2.currentStart >= c1.currentStart) {
            return Long.MAX_VALUE;
        }
        return c2.atLeast - c1.currentStart;
    }

    class Block {
        int l, r;
        long currentAdd;
        Cell[] cells;
        Cell[] stack;
        int stackSize;

        void buildStack() {
            System.arraycopy(cells, 0, stack, 0, cells.length);
            Arrays.sort(stack, new Comparator<Cell>() {
                @Override
                public int compare(Cell o1, Cell o2) {
                    return Long.compare(o1.atLeast, o2.atLeast);
                }
            });
            stackSize = 1;
            for (int i = 1; i < cells.length; i++) {
                Cell last = stack[stackSize - 1];
                Cell newOne = stack[i];
                long t1 = whenSecondSmaller(last, newOne);
                if (t1 == Long.MAX_VALUE) {
                    continue;
                }
                while (stackSize >= 2) {
                    Cell p2 = stack[stackSize - 2];
                    Cell p1 = stack[stackSize - 1];
                    long tP1P2 = whenSecondSmaller(p2, p1);
                    long myT = whenSecondSmaller(p1, newOne);
                    if (myT <= tP1P2) {
                        stackSize--;
                    } else {
                        break;
                    }
                }
                stack[stackSize++] = newOne;
            }
        }

        long getMinInStack() {
            if (stackSize == 1 || whenSecondSmaller(stack[0], stack[1]) >= currentAdd) {
                return stack[0].getValue(currentAdd);
            }
            int l = 0, r = stackSize - 1;
            while (r - l > 1) {
                int m = (l + r) >> 1;
                Cell c1 = stack[m], c2 = stack[m + 1];
                long t = whenSecondSmaller(c1, c2);
                if (t > currentAdd) {
                    r = m;
                } else {
                    l = m;
                }
            }
            return stack[r].getValue(currentAdd);
        }

        long getMin(int lQuery, int rQuery) {
            if (lQuery > r || rQuery < l) {
                return Long.MAX_VALUE;
            }
            if (lQuery <= l && rQuery >= r) {
                return getMinInStack();
            }
            long min = Long.MAX_VALUE;
            for (Cell c : cells) {
                if (c.pos >= lQuery && c.pos <= rQuery) {
                    min = Math.min(min, c.getValue(currentAdd));
                }
            }
            return min;
        }

        void add(int lQuery, int rQuery, long delta) {
            if (lQuery > r || rQuery < l) {
                return;
            }
            if (lQuery <= l && rQuery >= r) {
                currentAdd += delta;
                return;
            }
            for (Cell c : cells) {
                if (c.pos >= lQuery && c.pos <= rQuery) {
                    c.currentStart += delta;
                }
            }
            buildStack();
        }

        Block(long[] currentStart, long[] atLeast, int l, int r) {
            this.l = l;
            this.r = r;
            cells = new Cell[r - l + 1];
            for (int i = 0; i < cells.length; i++) {
                int pos = l + i;
                cells[i] = new Cell(currentStart[pos], atLeast[pos], pos);
            }
            stack = new Cell[cells.length];
            buildStack();
        }

    }

    void solve() {
        int n = in.nextInt();
        int q = in.nextInt();
        long[] expected = new long[n];
        long[] current = new long[n];
        for (int i = 0; i < n; i++) {
            current[i] = in.nextLong();
            expected[i] = in.nextLong();
        }
        final int SQRT = 150;
        Block[] blocks = new Block[(n + SQRT - 1) / SQRT];
        for (int i = 0; i < blocks.length; i++) {
            int from = i * SQRT;
            int to = Math.min(n, (i + 1) * SQRT) - 1;
            blocks[i] = new Block(current, expected, from, to);
        }
        for (int i = 0; i < q; i++) {
            if (in.nextInt() == 1) {
                int left = in.nextInt() - 1, right = in.nextInt() - 1;
                int delta = in.nextInt();
                for (Block b : blocks) {
                    b.add(left, right, delta);
                }
            } else {
                int left = in.nextInt() - 1, right = in.nextInt() - 1;
                long min = Long.MAX_VALUE;
                for (Block b : blocks) {
                    min = Math.min(b.getMin(left, right), min);
                }
                out.println(min);
            }
        }
    }

    void run() {
        try {
            in = new FastScanner(new File("Sol.in"));
            out = new PrintWriter(new File("Sol.out"));

            solve();

            out.close();
        } catch (FileNotFoundException e) {
            e.printStackTrace();
        }
    }

    void runIO() {

        in = new FastScanner(System.in);
        out = new PrintWriter(System.out);

        solve();

        out.close();
    }

    class FastScanner {
        BufferedReader br;
        StringTokenizer st;

        public FastScanner(File f) {
            try {
                br = new BufferedReader(new FileReader(f));
            } catch (FileNotFoundException e) {
                e.printStackTrace();
            }
        }

        public FastScanner(InputStream f) {
            br = new BufferedReader(new InputStreamReader(f));
        }

        String next() {
            while (st == null || !st.hasMoreTokens()) {
                String s = null;
                try {
                    s = br.readLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (s == null)
                    return null;
                st = new StringTokenizer(s);
            }
            return st.nextToken();
        }

        boolean hasMoreTokens() {
            while (st == null || !st.hasMoreTokens()) {
                String s = null;
                try {
                    s = br.readLine();
                } catch (IOException e) {
                    e.printStackTrace();
                }
                if (s == null)
                    return false;
                st = new StringTokenizer(s);
            }
            return true;
        }

        int nextInt() {
            return Integer.parseInt(next());
        }

        long nextLong() {
            return Long.parseLong(next());
        }

        double nextDouble() {
            return Double.parseDouble(next());
        }
    }

    public static void main(String[] args) {
        new SolSqrt().runIO();
    }
}